Early Radiographic Healing and Functional Results After Autologous Osteochondral Grafting for Osteochondritis Dissecans of the Capitellum: Introduction of a New Magnetic Resonance Imaging-Based Scoring System.

BACKGROUND

Autologous osteochondral grafting (OG) is an option in the treatment of capitellar osteochondritis dissecans (COCD). However, radiographic healing after this procedure has not been well documented.

PURPOSE

To develop a magnetic resonance imaging (MRI)-based scoring system specific for evaluating healing after single-plug OG in COCD and to evaluate correlation between radiographic healing and early clinical outcomes.

STUDY DESIGN

Cohort study (diagnosis); Level of evidence, 3.

METHODS

Between 2014 and 2017, 183 elbows with COCD were enrolled in a prospective registry. A total of 61 elbows in 59 patients underwent single-plug OG. Of these, 52 elbows in 50 patients had pre- and postoperative MRI scans. Postoperative MRI and clinical outcome data from this group were used to develop the novel BOGIE score (Boston Osteochondral Graft Incorporation in the Elbow), with a possible range of 4 to 12.

RESULTS

Median age at surgery was 14.2 years (interquartile range, 13.1-15.0 years). Median clinical follow-up after OG was 12.4 months (interquartile range, 9.5-16.9 months; range, 6-53 months). Compared with before surgery, elbow function at 6 months after surgery and at latest follow-up was significantly improved as measured by the Timmerman and Andrews score (TAS; median: 145 before surgery, 185 at 6 months after surgery, 190 at latest follow-up; < .001, before vs after surgery), as well as the short version of Disabilities of the Arm, Shoulder and Hand score; median: 21 before surgery, 7 at 6 months after surgery, and 0 at latest follow-up; < .001 before surgery vs after surgery). Median BOGIE score at 6 months after surgery was 10 (range, 4-12). BOGIE score intraobserver reliability was 0.90 (95% CI, 0.82-0.94) for reader 1 and 0.91 (95% CI, 0.86-0.95) for reader 2. Interobserver reliability between the readers was 0.86 (95% CI, 0.78-0.92). Correlation was observed between the 6-month BOGIE score and the concurrent postoperative objective TAS ( < .001) as well as total TAS ( = .01) but not the subjective TAS ( = .08). Patients who underwent subsequent secondary surgery for persistent symptoms had a significantly lower postoperative BOGIE score at 6 months than those who did not (median, 7.8 vs 10.3; = .016).

CONCLUSION

Quantitative evaluation for radiologic healing after single-plug OG in COCD is possible. The MRI-based BOGIE score appears to correlate with early clinical function and may be useful as an adjunct tool in decision making on activity progression. The use of a standardized MRI score may improve comparability of outcomes after OG in the literature.